Rotary hydraulic swivel



July 3, 1951 l.. w. STAHL ETAL ROTARY HYDRAULIC SWIVEL FiledJune 23, 1947 my gia 1 July 3, 1951 w. STAHL ET AL 2,558,990

ROTARY HYDRAULIC swIvRr.

Filed June 23, 1947 2 sheets-sheet 2 Patented July 3, 1951 UNITED STATES PATENT OFFICE ROTARY HYDRAULIC SWIVEL Application June 23, 3.947, Serial No. 756,378

8 Claims. l

The invention relates to rotary hydraulic swivels, more particularly of the type used in well drilling operations.

One object of the invention is to provide an improved rotary hydraulic swivel which includes rotatable and non-rotatable fluid conducting elements communicatively connected by a Boating tube or pipe section which is not rigidly attached to either of the elements, and demount-v able packing assemblies with sealing means between both ends of the tube and said elements.

Another object of the invention is to provide a hydraulic swivel which comprises rotatable and non-rotatable elements and a tube communicatively connected to the elements, and unitary packing assemblies at the ends of the tube which are readily demountable with the tube for unitary lateral withdrawal from the space between the elements.

Another object of the invention is to provide a hydraulic swivel of this type in which the floating tube is carried in the packing devices and is free for self-positioning between axially misaligned non-rotatable and rotatable elements.

Another object of the invention is to provide a hydraulic swivel of this type, with demountable packing devices which contain sealing rings and means for lubricating them.

Another object of the invention is to provide a hydraulic swivel of this type, in which the tube and packing devices are reversible end-to-end between the non-rotatable and rotatable elements.

Other objects of the invention will appear from the detailed description.

The invention consists in the several novel features hereinafter set forth, and more particularly dened by claims at the conclusion hereof.

In the drawings:

Fig. 1 is a vertical section of a rotary hydraulic swivel, exemplifying the invention.

Fig. 2 is a section upon a larger scale, of the ends of non-rotating and rotating elements of the swivel, the tube communicatively connecting them, and the packing devices for providing fluid-tight seals between said elements and the tube.

Fig. 3 is a section taken on line 3-3 of Fig. 2.

Fig. l is a section illustrating a modification of the invention.

The invention is exemplified in a hydraulic swivel which comprises a rotatable tubular stem II]v which is usually driven by a rotary table and connected to the upper end of a pipe which conducts wash fluid to a drilling tool at its lower end, as well understood in the art. The upper end of stem I0 extends through a casing I6 which is supported by a bail I2 which is connected to trunnions I8 which are mounted in said casing. Bail I2 is usually supported by a cable hoist for raising and lowering the swivel. Rotatable stem Il] is journalled in a main thrust bearing I2, radial bearings I3, and an upthrust bearing I4 of the anti-friction type, for rotation in casing I6. A bonnet 20 includes a head 22 which forms a closure for the top of casing I6. The bonnet 20 includes an annulus 24 at its upper end. A gooseneck 26 has an annular flange 28 which is secured by bolts 2l, to the top of bonnet 20 and is supported from casing I6 by said bonnet. Fluid for delivery to the drill pipe, is conducted to the offset portion of the gooseneck by the usual flexible pipe (not shown) for delivering wash fluid through the gooseneck to stem I!) and the drill pipe. The gooseneck exemplifies a non-rotatable element of the swivel, and the stem I0 a rotatable element thereof. A replaceable bushing 32 is secured in the upper end of stem IE) and a similar bushing 33 is secured in the lower end of gooseneck 26.

The lower end of gooseneck 26 which extends through annulus 24 of bonnet 2D, and the upper end of the rotatable stem, are spaced apart vertically and are communicatively connected for the flow of wash fluid from the gooseneck into the bore of stem I0 by a demountable tube or pipe section 38. Demountable unitary packing assemblies or devices which include sealing rings, are provided between the upper and lower ends of tube 38 and gooseneck 26 and stem I B, respectively, for preventing escape of fluid. Tube 38 is floatingly held between gooseneck 26 and stem Il! and is free to rotate withA the rotatable packing device on the lower end of tube 33 which is connected to stem I0, or to permit the tube to remain stationary with the packing device on the nonrotatable gooseneck 26. This tube 38 exemplifies a fluid conducting element which is rotatable relatively to the gooseneck 26, or relatively to stem It. In this construction, the wear is distributed between the contacting surfaces of the sealing rings which are of eXible and absorbent material, and said tube. This construction also supports the tube so itis free to positionA itself to compensate for any axial misalignment of the elements and the tube while maintaining the fluid seals. The two demountable packing devices containing the sealing rings, may be unitarily removed laterally with tube 38 and independently of the gooseneck and stem '18. The packing devices are provided with means for introducing lubricant between the contact surfaces of the tube and the sealing rings, for lubricating said Contact surfaces. These packing devices are alike in construction, so that they may be interchangeably and demountably attached to the non-rotatable gooseneck 26 and the stem I0. These packing devices, when detached from the gooseneck 26 and stem I6, respectively, are slidable together on the tube 38, so that the tube and packing devices may be unitarily removed laterally from between the gooseneck and stem. For this purpose, the overall height of the packing devices when moved together on tube 38, is less than the space between gooseneck 26 and stem IIJ.

Each packing device consists of a unitary assembly which comprises a collar 40 which is vprovided with a screw thread 4l whereby it may be demountably attached to the lower end of gooseneck 26 or to the stem l0, which are provided with corresponding screw threads. Each collar 40 is provided with sockets 401 which are adapted to receive a bar for rotating the collar onto or oil the fluid conducting elements. A replaceable bushing 42 Vwhich is angular in crosssection, is seated against an annular shoulder 43 in the posterior end of each collar. An oil distributing ring 44 is seated against an internal shoulder 45 in collar 40, and is secured against said shoulder by a gland 46 which is screwthreaded into collar 48. A sealing ring of ilexible and resilient packing material, 49, is confined between ring 44 and bushing 42, and a similar sealing ring 50 is confined between ring 44 and gland 46. Bushings 42 and 46 are bored to leave clearance around tube 38, so that the sealing rings 49 and 59 will form the contacting surfaces between tube 38 and the packing devices. As a result, tube 38 will contact adjacent its ends, mainly with the inner periphery of sealing rings 49 and 58 so that the tube may remain stationary with the gooseneck 26 or rotate with stem I0, and so that the wear will be distributed to the contact surfaces between tube 38 and the sealing rings in both packing devices, and the tube will be free to position itself in the sealing rings and compensate for axial misalignment of gooseneck 26 and stem I6 while maintaining the fluid seals. A ring 34 of resilient packing between bushing 33 and stem I0, forms a seal between stem I8 and the collar 48 ofthe lower packing device. A ring 35 of resilient packing between bushing 32 and gooseneck 26, forms a seal between said gooseneck and the collar 40 of the upper packing device. V

In the operation of theseY hydraulic swivels which include a floating tube, it is advantageous to keep the sealing rings well lubricated for preventing wear. A series of suitable fittings 52 are screw-threaded into each collar 40, for introducing lubricant for the sealing rings 49 and 50, into an annular space 69 in collar 40 around ring 44. Radial ports 18 extend through each oil ring 44 and conduct lubricant to a channel 'I2 around tube 38. Axial ports 'fl in tube 38 have' their ends communicatively connected to channels 'i2 in the upper and lower packing devices. From each channel 'l2 lubricant flows to the associated sealing rings 49 and 56. Each ring 49 and 59 is provided with an annular groove i which provides pressure scaling lips when uid Y* Y, or lubricant is introduced under pressure,

During a drilling operation, the Wash uid delivered into gooseneck 26 will flow through tube 38 into the rotatable stem I0 and to the drill pipe. The packing devices prevent the escape of fluid at the junctures of tube 38 with gooseneck 26 and stem I0. Tube 38, the ends of which contact with the lubricated rings 49 and 50 in the packing device on the non-rotatable gooseneck, and the lubricated rings 49 and 50 in the packing device which rotates with stem I8, will be floating or free to remain stationary with gooseneck 26, or rotate with stem I0, or rotatably slip relatively to both packing devices. This distributes the wear on the contact surfaces between tube 38 and the sealing rings, and tube 38 is free to position itself Within the sealing rings to compensate for axial misalignment of the gooseneck 26 and stem I0 while maintaining the fluid seals. When for any purpose it is desired to remove tube 38 for repair or replacement of the packing devices, or the sealing rings, it is only necessary to unscrew collars 40 from gooseneck 26 andy from stem I0 and move the packing devices together, as illustratedV in dotted lines in Fig. 2. Tube 38 and the packing devices can then be unitarily removed laterally from the space between gooseneck 26 and stem Ill. This may be done while the gooseneck remains secured to bonnet 20, and stem I6 remains journalled in casing I6, and greatly facilitates the removal and replacement of tube 38 and the packing assemblies. When the tube and packing assemblies have beenthus removed, the packing assemblies may be readily slipped off the ends of the tube, for repair or replacement of their parts. In replacing the tube and packing devices, the assembled tube 38 and Vthe 'packing devices may be laterally inserted between gooseneck 26 and stem I0, and the coupling collars 48 may be readily secured in operative position. Ihe packing devices and tube are end- Wise reversible for interchangeably securing the packing devices to the gooseneck 26 and stem Il).

The invention exemplilles a hydraulic swivel for drilling. operations which includes a lloating tube between the non-rotatable and rotatable fluid conducting elements and self-contained packing assemblies including lubricated sealing rings which are readily demountable with the tube, without disturbing the connections between the gooseneck and its supporting bonnet; which provides for distribution of Wear on the contacting areas of the tube and the sealing ring; which does not require accurate axial alignment of the non-rotatable and rotatable lluid conducing elements for maintaining the fluid seals; and which is simple in constructionV and efficient in operation.

The invention is not to be understood as limited to the details described, since these may be modified within the scope of the appended claims Without departing from the spirit or scope of the invention. Y

Having thus described the invention, what We claim as new and desire to secure by Letters Patent is:

l. A hydraulic rotary swivel, comprising: nonrotatable and rotatable fluid conducting elements; a floating tube for conducting fluid and interposed between said elements and separable therefrom and demountable packing-assemblies around the ends of the tube, respectively; each assembly including sealing means around the tube and a member provided with means for detachably attaching the assembly of which it is a part, to vone of said elements, the sealing means of each assembly having contact with the tube which leaves it free to rotate or remain stationary during operation of the swivel, said members being movable toward each other on the tube when they are uncoupled from said element.

2. A hydraulic rotary swivel, comprising: nonrotatable and rotatable iluid conducting elements; a floating tube for conducting iluid and interposed between said elements and separable therefrom and demountable packing-assemblies around the ends of the tube, respectively; each assembly including sealing means around the tube and a collar provided with a screw-thread for detachably attaching the assembly of which it is a part, to one of said elements, the sealing means of each assembly having contact with the tube which leaves it free to rotate or remain stationary during operation of the swivel, said collars being movable toward each other when they are uncoupled from said elements.

3. A hydraulic rotary swivel, comprising: nonrotatable and rotatable fluid conducting elements; a floating tube for conducting fluid and interposed between said elements and separable therefrom and demountable packing-assemblies around the ends of the tube, respectively; each assembly including a sealing ring around the tube, a collar provided with means for detachably attaching the assembly of which it is a part, to one of said elements, and a gland in the collar, the sealing means of each assembly having contact with the tube which leaves it freet/o rotate or remain stationary during operation of the swivel, said collars being movable toward each other along the tube when they are uncoupled from said elements.

4. A hydraulic rotary swivel comprising: nonrotatable and rotatable fluid conducting elements; a floating tube for conducting fluid and interposed between said elements and separable therefrom and demountable packing-assemblies around the ends of the tube, respectively; each assembly including a plurality of sealing rings around the tube, a collar around said rings, provided with means for detachably attaching the assembly of which it is a part, to one of said elements, a bushing in the collar, and a gland in the collar for said rings, the sealing rings of each assembly having contact with the tube which leaves it free to rotate or remain stationary during operation of the swivel.

5. A hydraulic rotary swivel comprising: nonrotatable and rotatable fluid conducting elements; a tube for conducting fluid and interposed between said elements and separable therefrom; and packing-assemblies adjacent the ends of the tube, respectively, each assembly including annular packing means contacting the tube and a member provided with means for demcuntably attaching the assembly oi which it is a part, to one of said elements, said members being movable toward each other longitudinally of the tube to clear the elements for unitary removal of the tube and the assemblies laterally from the elements, said tube and packing-assemblies being endwise reversible for connection to either of said elements.

6. A packing assembly for a hydraulic rotary swivel including non-rotatable and rotatable fluid conducting elements and a tube for conducting uid between said elements and separable therefrom, comprising: a collar provided with means for demountably attaching the assembly to one of .said elements, a packing ring in the collar and contacting the tube, and a packing-retaining gland inwardly of the ends of the collar and abutting one of said elements.

7. A packing assembly for a hydraulic rotary swivel including non-rotatable and rotatable iluid conducting elements and a tube for conducting fluid between said elements and separable therefrom, comprising: a collar provided with means for demcuntably attaching the assembly to one of said elements, a packing ring in the collar and contacting the tube, a bushing at the outer end of the collar, and a packing-retaining gland inwardly of the ends of the collar.

8. A packing assembly for a hydraulic rotary swivel including non-rotatable and rotatable uid conducting elements and a tube for conducting iluid between said elements and separable therefrom, comprising: a collar provided with means for demountably attaching the assembly to one of said elements, a plurality of packing rings contacting the tube, a bushing at the outer end of the collar, and a packing-retaining gland inwardly of the ends of the collar for retaining the packing ring.

LESLIE W. STAHL. HARRY E. YOUNG, Ja.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 852,580 Rutherford May 7, 1907 1,670,368 MacPherson May 22, 1928 2,227,105 Pritchard Dec. 31, 1940 2,237,715 Shaw et al. Apr. 8, 1941 2,379,035 Phillips June 26, 1945 

